Figure 3.

Altered ATP levels seen in DKO cells but no difference in mitochondrial activity. A, respirometric analysis of oxygen consumption over time, with addition of mitochondrial modulators. B, images of live cells treated with MitoTracker (shown in green). Nuclei were stained with Hoechst (blue). Scale bars, 15 μm. C, Western blotting using antibodies against members of the five electron transport chain complexes, plus actin as loading control. D, HPLC analysis of adenine nucleotides. E, adenylate energy charge ((ATP + 0.5 ADP)/(ATP + ADP + AMP)) derived from HPLC results in D. F, Western blotting for LKB1, total and phosphorylated AMPK (Thr¹⁷²), and actin. Quantified by densitometry (right). Blot is representative of 4 experiments. ***, p < 0.001, t test. Respirometry in A, images in B and blot in C are representative of 3 experiments. Bar chart in A shows mean ± S.D. from 3 experiments. HPLC data in D and E show mean ± S.D. from 6 experiments. *, p < 0.05, ANOVA with Tukey post test. max unc., maximum uncoupled rate.